Perishable goods may be packed in containers for shipping that utilize materials such as waxed corrugate and expanded foam. A refrigerant may be placed in the container with the goods. For example, it is known to pack fresh fish in a bag, surround the bag with a frozen Gel-Pack or ice, and place the bag and refrigerant in a corrugated container lined with polystyrene insulation. While such a thermally insulated container will keep the container contents acceptably refrigerated for a period of time, shipping times may exceed this time period. Further, the materials used for the containers, and especially expanded foam materials, give rise to environmental concerns.
U.S. Pat. No. 5,000,372 and U.S. Pat. No. 5,111,957 attempt to improve the insulating properties of a container by using panels formed of a honeycomb material covered by aluminum foil. However, there is a risk of leakage and there also remains a need for a thermal container which maintains its contents in a refrigerated state for a longer time period.